Khmer font previewer
Your own words, in every Khmer web font, at the size you will actually use.
A specimen image is not a preview
Khmer stacks. Subscript consonants hang below the line and vowel marks sit above it, so a typeface that looks elegant in a one-word specimen can collide with itself in a paragraph at 16 pixels.
The only honest test is your sentence, at your size, with your line height. That is all this page is — the fonts are loaded properly and your text is drawn in each of them.
Display faces are not body faces
Moul, Koulen, Bokor and Taprom are drawn for one line at a large size. They are the most common mistake in Khmer web design: chosen from a logo, applied to a paragraph, and unreadable by the second sentence.
For text people have to read, start with Noto Sans Khmer, Battambang or Kantumruy Pro. Keep the decorative face for the heading, where it earns its keep.
Khmer needs more line height
Because of the marks above and the subscripts below, Khmer needs noticeably more space between lines than Latin does. A line height of 1.5 that looks generous in English is tight in Khmer, and around 1.8 is where rows stop touching.
The slider here exists for that. Set it until the paragraph breathes, then use that number in your CSS rather than whatever your theme shipped with.
Mixing Khmer and English
Most Cambodian sites do. Name the Khmer font first in your font stack and let the Latin fall through to a system font, or pick a Khmer face whose Latin you actually like — several of these draw both, and not all of them draw both well.
Check the numbers too. Khmer digits and Arabic digits often come from different parts of the font, and a price list is where a mismatch shows up most.